Plasma processing device

Abstract

A plasma processing device includes an upper electrode assembly and a lower electrode assembly. The upper electrode assembly has a plurality of post electrodes, made of a conductive material, protruding individually out of one surface of the upper electrode assembly, and connected to a plasma source. A plasma deficiency area having no post electrode is disposed in a center portion of the upper electrode assembly. The plurality of post electrodes are disposed in a ringlike electrode distribution area surrounding concentrically the plasma deficiency area. The lower electrode assembly is rotatable, made of a conducting material, and covered by a dielectric material.

What is claimed is: 
     
         1 . A plasma processing device, comprising:
 an upper electrode assembly, including a plurality of post electrodes protruding toward a lower electrode assembly from a reaction surface of the upper electrode assembly, the plurality of post electrodes being connected with a plasma power source, a plasma deficiency area being defined in a central area of the upper electrode assembly where none of the plurality of post electrodes is located, an annular electrode distribution area being defined between a boundary of the plasma deficiency area and a smallest circumference encircling all the plurality of post electrodes, an upper plasma-generating region being formed under the plurality of post electrodes with respect to the annular electrode distribution area; and   the lower electrode assembly, located under and separated from the upper electrode assembly, having at least one built-in type electrode coated by a dielectric material, being grounded and rotatable;   wherein a plasma-reaction zone including the plasma-generating region is formed between the upper electrode assembly and the lower electrode assembly.   
     
     
         2 . The plasma processing device of  claim 1 , wherein the at least one built-in type electrode is at least circularly arranged, an lower annular plasma-generating area is defined by revolving the at least one built-in type electrode, a concentric circular empty area defined inside the lower annular plasma-generating area is located in correspondence with the plasma deficiency area, and an outer diameter of the lower annular plasma-generating area is no less than another outer diameter of the annular electrode distribution area. 
     
     
         3 . The plasma processing device of  claim 2 , wherein the at least one built-in type electrode is annular shaped, and an inner diameter of the lower annular plasma-generating area is no more than another inner diameter of the annular electrode distribution area. 
     
     
         4 . The plasma processing device of  claim 2 , wherein the at least one built-in type electrode is consisted of a plurality of solid disks circularly arranged. 
     
     
         5 . The plasma processing device of  claim 2 , wherein a diameter of the at least one built-in type electrode is no less than that of a workpiece to be processed by the corresponding built-in type electrode. 
     
     
         6 . The plasma processing device of  claim 1 , wherein the upper electrode assembly includes a main body made of a conductive material, the plurality of post electrodes are located at one side of the main body, the main body is furnished with a first cooling channel, and an axial center of each of the plurality of post electrodes is furnished with a second cooling channel communicated spatially with the first cooling channel to form a cooling route. 
     
     
         7 . The plasma processing device of  claim 1 , wherein the plasma deficiency area is distributed with a plurality of vent holes. 
     
     
         8 . The plasma processing device of  claim 1 , further including a reaction shield located between the upper electrode assembly and the lower electrode assembly, wherein the reaction shield includes:
 a chamber, annular shaped to have an inner diameter larger than any of outer diameters of the upper electrode assembly and the lower electrode assembly, having at least one communicative hole;   a supportive frame, being hollow and annular, connected with the chamber; and   a drive device for moving the chamber and the supportive frame simultaneously.   
     
     
         9 . The plasma processing device of  claim 8 , wherein a continuous path for flowing a process gas is formed by integrating spatially the plurality of vent holes of upper electrode assembly, the plasma-reaction zone between the upper electrode assembly and the lower electrode assembly, the at least one communicative hole, and an interior of the chamber. 
     
     
         10 . The plasma processing device of  claim 9 , wherein one of the plurality of vent holes and the interior of the chamber is connected to a mixture tank of the process gas, while another thereof is connected to an exhaust-gas treatment system. 
     
     
         11 . The plasma processing device of  claim 8 , wherein the chamber is furnished with a valve to control in/out of the process gas with respect to the chamber. 
     
     
         12 . The plasma processing device of  claim 8 , wherein the drive device controls the chamber to reciprocally move in a direction parallel to a first direction between a process position and a material-loading/unloading position, and the first direction is parallel to an axial direction of one of the plurality of post electrodes but perpendicular to the water level; wherein, when the chamber moves to the process position, a lower edge of the chamber is flush with or lower than a lower surface of the lower electrode assembly; wherein, when the drive device lifts the chamber up to the material-loading/unloading position, the lower edge of the chamber is higher than a top surface of the lower electrode assembly. 
     
     
         13 . The plasma processing device of  claim 8 , wherein the chamber and the supportive frame are made of one of a metal and a dielectric material. 
     
     
         14 . The plasma processing device of  claim 1 , wherein any of the plurality of post electrodes is a conductive material coated by a dielectric material, and the plurality of post electrodes are arranged to surround a center so as to form a plurality of concentric circles, each of the plurality of concentric circles having at least one of the plurality of post electrodes. 
     
     
         15 . The plasma processing device of  claim 14 , including two neighboring concentric circles out of the plurality of concentric circles having the same quantity of the post electrodes. 
     
     
         16 . The plasma processing device of  claim 14 , wherein, in any two neighboring concentric circles of the plurality of concentric circles, a quantity of the post electrodes in an outer circle of the two neighboring concentric circles is bigger than another quantity of the post electrodes in an inner circle thereof. 
     
     
         17 . The plasma processing device of  claim 14 , wherein each of the plurality of concentric circles is accompanied by a trace ring generated by revolving the post electrodes in the same circle about the center, two said neighboring trace rings with respect to two said neighboring concentric circles are at least contacted to each other, and the annular electrode distribution area is formed by integrating all said trace rings of the plurality of concentric circles.